Apparatus to control the number of turns of the drawing shaft in drawing benches



L. BREGUET ET AL APPARATUS T0 CONTROL THE NUMBER OF TURNS OF THE DRAWING SHAFT IN DRAWING BENCHES Filed Dec. 11, 1925 Patented Feb. 9, 1926.

UNITED STATES PATENT OFFICE.

incurs BREGUET AND PAUL BREGUET, or GENEVA, SWITZERLAND.

APPARATUS: T0 CONTROL THE NUMBER OF TURNS OF THE IDRAWING SI-IAF'I I-N DRAWING BENCHES.

Application filed December 11,1923. Serial No. 680,047.

To all whom it may concern:

Beit known that we, LOUIS Bmiennr and PAUL BmieUE-r, citizens of Switzerland, residing at Geneva, 7% Rue de Carouge, Switzerland, have invented certain new and useful Improvements in Apparatus to Control the Number of Turns of the Drawing Shaft in Drawing Benches, of which the following is a specification.

The present invention relates to mechanism for controlling the rotation of the drawing shafts of wire-drawing apparatus; the term drawing shaft, as herein used, being intendedjto indicate the shaft of the drawing bench which drives the spools, pulleys or other elements employed to efiect the movement of the wire. If only one spool is utilized, the drawing shaft may be the shaft whereon such spool is mounted.

It is well known to those skilled in the art that the drawing of the Wire, or its winding, becomes more and more diflicult as the diameter of the wire decreases and the drawing velocity increases. The slightest variation in expansion may cause rupture of the wire, which may entail considerable loss of time, particularly inthe case of machines for manufacturing very fine wire; the rupture of the wire also impairing its quality.

The object of this invention is to provide, especially in line wire manufacturing,

' a means or mechanism for automatically controlling the velocity of the drawing shaft so as to constantly maintain the stress exerted on the wire as nearly as possible at a predetermined normal degree.

A11 embodiment of the inventionis illus trated in the accompanying drawing, in which Figure 1 is a perspective view of the improved controlling mechanism, and Fig. 2 is an enlarged view, in front elevation, of a detail.

Referring more particularly thereto, a indicates the drawing shaft and c a cone pulley on said shaft which is driven by a belt I), assumed to travel at a constant speed; the position of the belt on the cone being adjusted by means of a shifting fork n operated as hereinafter described. Shaft a carries the drawing spool 03 on which the Wire 6 is threaded afterhaving beenjled over a swlnging or vibrating roller f, the latter being mounted on the lower end of a rod 7 which extends downward from a horizontal determining the amplitude of a the swing.

The end of the shaft remote from that to which the pendulum is affixed has secured to it asemi-circular cam f designed to automatically control the rotation in either direction of 'a horizontal rock shaft Z having a threaded portion whereon is mounted a traveling nut or collar 12 carrying the shifting fo'rkm Hence, the axial movement of collar 11 in one direction or the other along shaft Z will produce a corresponding movement of the belt toward one or the other end of the cone 0 and, consequently, a change in the speed of the drawing shaft a.

The cam f forms part of the controllingmechanism wherein our invention primarily resides As shown in Fig. 2 the under faces of the two horns of the cam rest upon the up-turned inner ends of a pair of pawls i 11 which are centrally mounted upon pivot bolts 72, carried by lugs or projections h formed on the free end of the upper arm 5 of a bell-crank rocker loosely mounted at its apexon the rock-shaft Z. The lower or horizontal arm 71 of the rocker is connected by a rod m -f'with an eccentric m which is continuously rotated in any desired manner, so that the rocker will thus be subjected to a constant swinging movement, as will be understood. The outer portions or tails of the pawls are connectedby retractile springs s with the corresponding parts of a second pair of pawls h h which are mounted on bolts 7L9 carried by the rocker arm 2', and the inner ends of these pawls' h h cngage the upper ends of a third pair of 'pawls if, h, mounted on pivot bolts it fixed to arm 71; the lower arms of the third pair being'connected by a retractile spring 3 The lastnamed pawls have the free ends of their lower arms designed for coaction with a pair of ratchet wheels 72 and the teeth of which are inclined in opposite directions;

said wheels being keyed to the rock-shaft Z so as to impart a. rocking movement thereto in one direction or they other, according as one ratchet or the other is positively rotated.

The mechanism just described acts, therefore, in much the same way as a pendulum: controlled driving device or escapement; that is to say, when the tension of the wire upon the roller f or pendulum weight exceeds a predetermined normal.-which is the tension for which the mechanism has originally'been set by the adjustment of weight g the pendulum will be forced inward and will produce a clockwise rotation of shaft f and when the tension falls, below such normal, the pendulum swiiigs outward and rotates shaft 7 anti-clockwise. Inboth cases, the rotation of said shaft entails a lateral movement of the shifting fork 01 12 to one side or the other on" shaft Z-v and a resultant movement of the driving belt along cone 0; the movement of the fork being caused by the rotation of shaft Z which isproduced by the operation of the escapement. If the tension of the wire coincides;

with the aforesaid predetermined normal,

then the pendulinn or controller willfremain stationary, andthe escapement will not be actuated. I

V In the first. of the three cases mentioned, the clockwise rocking movement of the controller shaft 7 will produce'a similarmovement of the cam f thereon, and the righthand horn of'said cam will depress the inner arm of the adjacent pawl k the latter, through its spring connection .9, rocking pawl k anti-clockwise and, in consequence, causing the inner arm of said pawl I14 to act, in turn, upon pawl 72, to disengage f-rom' ratchet 7: 7 Through the same movement of cam i coupled with the action of the springs s, s", the lefthand pawl 71, is en-' gaged with ratchet Z0 and, during the succeeding movement of the rocker, turns shaft Z anti-clockwise, thereby producing a lefthand movement of the shifting fork and a movement of belt Z) toward the larger end ofcone 0, thus reducing the speed of the drawing shaft.

In the second case, where the tension drops below normal, the reverse operations take place. Pendulum 7, f moves outward and produces an anti-clockwise, rotation of.

shaft f and its cam f this movement of the cam effecting the disengagement ofipawl 71. from ratchet 70 and the engagement of pawl it with ratchetia with the result that shaft Z is rotated clockwise, fork a, n moves rightward thereon, and belt 6 moves toward the smaller end of cone 0 and drives shaft a at an increasing speed.

In the third case, where the tension is and 72, out of engagement with their respective ratchets. Hence the bell-crank rocker will oscillate idly without producing any rotation of shaft Z. This pendulum operated escapement is such a sensitive controller 'of the speed that fine wire manufacturing becomes a good deal less troublesome because less loss by waste will be occasioned and much time saved.

It'will be understood that the rocker, the set, of pawls thereon, and the eccentric m and its connecting rod m conjointly form an auxiliary driving device or servo-metor which is utilized to effect the automatic shifting of the belt 6; this servomotor being entirely independent of the drawing shaft so that the power necessary for the belt-shifting operation is no longer required to be taken from said shaft. This means, also, that. the wire is relieved from the strain needed to overcome the working of the beltshifter, that less breaks of wire will occur, and that the use of a servo-motor for operating' the change-Speed device can hardly be dispensed with in fine wire manufacturing. servo-motor, has been illustrated herein, an electric, pneumatic or other type of driving device or motor might be substituted, and the rocker. may be operated otherwise than by a pendulum. Other and further modifications and changes might also be, made within the scope ofthe invention.

We claim:

1'. In a wire-drawing bench, the combination of a drawing shaft; a cone pulley thereon; a driving belt passing around the pulley;a belt shifter engaged with said belt to move it toward either end of said pulley; an independent mechanism for moving the belt shifter in either direction; ,a pendulum controlled by. the strain of the wire for starting saidmechanism; and a weighted lever for counter balancing the pendulum.

2. Ina wire-drawing bench, the combination ofa drawing shaft; a cone pulley thereon; a driving belt passing around the pulley; a belt shifter engaged with said belt to move it toward either end of said pulley; a shaft having a threaded portion whereon said shifter is mounted to travel; a pair of escapement wheelsfixed tothe second-named shaft tofelfect rightand left-hand rotation thereof; anangular rocker loosely, mounted on said second-named shaft 3 pawls carried However, whilethe preferred form of I by said rocker for alternative engagement thereby slaoken or decrease the speed of the with said Wheels; independent driving drawing shaft. means connected to operate said rocker; a In testimony whereof We aflix our sig- 1 third shaft; a two-horned cam fixed to the natures.

third shaft to throw out either awl; and a pendulum forming a feeler arm ioithe Wire LOUIS R to control the position of ,said cam and p PAUL BREGUET. 

